Calibration of depth cameras that use triangulation may be performed using special test charts. In some examples, features of a test chart may be known in advance. The distance to the chart and its orientation relative to one of the stereo cameras can be derived based solely on that camera. For example, the size of the squares may be proportional to the distance to the target. In addition, the warpage or distortion of the squares may be proportional to the angle between the reference camera and the target. Once the relative position of the test chart is known, errors in the depth may be measured using the stereo pair and camera parameters including pointing direction can be modified to reduce the resulting errors in depth output.
The same numbers are used throughout the disclosure and the figures to reference like components and features. Numbers in the 100 series refer to features originally found in FIG. 1; numbers in the 200 series refer to features originally found in FIG. 2; and so on.